Basics on REE

Rare Earth Elements (REE) are 17 elements including 15 lanthanides (La to Lu), scandium and yttrium. They share many of their properties, both chemical and physical and they naturally occur together in various types of mineral deposits. Rare earth elements are relatively abundant in the Earth’s crust, however they are usually not concentrated in economically exploitable ores.

Current estimates of available reserves exceed annual world production by three orders of magnitude.

Sources of REE

World resources are primarily coming from minerals bastnäsite and monazite. Bastnäsite ( China and USA) provides the largest percentage of the world's production. Monazite deposits (Australia, South America, China, India, Malaysia, South Africa, and others) are the second largest. Other important REE-bearing minerals include apatite, cheralite, eudialyte, loparite, phosphorites, REE-bearing clays, spent uranium solutions, and xenotime.

In addition to the primary sources and leaving aside recycling of REE from end-of-life products as other source, tailings and other by-products from previous mining activities may also hold significant amounts of REE.